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Gold-tone copper shaft coupler, 20 by 9 mm, with four screws

Unique-Bargains

Unique-Bargains Shaft Coupler 2mm x 4mm Gold Tone

SKU CH-ZCYX-J6E2V

Connects 2 mm and 4 mm motor shafts in RC planes or boats using a 20 mm copper coupler with four M3 screws

  • Size/Dimensions20 x 9mm / 0.79 inch x 0.35 inch (L*D)
  • Connects 2 mm and 4 mm shafts for flexible RC builds
  • Gold-tone copper body resists corrosion in marine models
  • Compact 20 × 9 mm profile fits tight motor mounts
  • M3 thread with four screws ensures secure installation
  • Lightweight 9 g design keeps aircraft balance optimal

Precision shaft coupling

The Unique-Bargains coupler joins a 2mm motor shaft to a 4mm driven shaft in RC airplanes and boats. Its copper body and M3 thread provide a secure mechanical link for small electric power systems.

Capacity and limits

The adapter accepts shafts from .08 to .16 inch diameter and transmits torque through four included set screws. It suits lightweight models but will not accommodate larger shafts or high-torque applications beyond its 20mm length.

Build and daily use

Gold-tone copper construction resists corrosion while the compact .79 by .35 inch profile fits tight motor mounts. The supplied screws allow quick installation and removal for routine maintenance or propeller changes.

Highlights

  • Connects 2 mm and 4 mm shafts for flexible RC builds
  • Gold-tone copper body resists corrosion in marine models
  • Compact 20 × 9 mm profile fits tight motor mounts
  • M3 thread with four screws ensures secure installation
  • Lightweight 9 g design keeps aircraft balance optimal

Specifications

Size/Dimensions20 x 9mm / 0.79 inch x 0.35 inch (L*D)
BrandUnique Bargains

Questions about this item

Will the 2mm to 4mm shaft range on this coupler fit the motor and propeller shafts I already have on my RC airplane?

The coupler connects a 2mm shaft on one side to a 4mm shaft on the other, so it matches motors and propellers with those exact diameters.

How can I confirm the M3 thread screws are holding the coupler securely after installation?

Tighten the four included M3 screws until the coupler does not rotate independently on either shaft and there is no axial play when you push or pull the motor.

Does the package include the four M3 mounting screws, or do I need to buy them separately?

The box contains one gold-tone copper shaft coupler measuring 20 x 9mm and four M3 screws, so no extra fasteners are required.

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